A known machine of this type comprises a frame consisting of a central part which carries two raking wheels and two lateral parts each of which carries a single raking wheel. For transport, each of the lateral parts can be rotated upwardly by an angle of about 90.degree.. This rotation is performed round a pivot pin connecting each of the lateral parts to the central part of the frame. A hydraulic jack causes the rotation. In the transport position, the width of the machine is reduced in relation to the work position. However, the bulk of the machine is still relatively large, especially for moving on roads and for storage. Moreover, the work forks on the raking wheels are directed outwardly when the lateral parts are in the transport position. Thus, the work forks can cause considerable damage and injuries to anything (such as vehicles, human beings, or animals) which comes into contact with them, both when moving and when at rest.